President Trump said today he has made up his mind on whether to exit the Iran nuclear deal. He would not say what his decision is. The 2-year-old agreement limits Iran's nuclear program in exchange for sanctions relief. If it unravels, it could affect the company Boeing, which has deals with the Islamic Republic for passenger planes worth billions of dollars. NPR's Jackie Northam reports.

JACKIE NORTHAM, BYLINE: The Iran nuclear deal allows Western aircraft manufacturers like Boeing to sell planes to Iran. The need is huge. Iran is still using Boeing jets from the 1970s. Boeing has moved quickly, inking deals for aircraft worth nearly $20 billion. Its main competitor, the Paris-based Airbus, has locked in more than double that. Zachary Goldman is with New York University School of Law and worked on Iran sanctions at the Treasury Department. He says the deal doesn't just affect Boeing.

ZACHARY GOLDMAN: But also the suppliers and subcontractors and sub-subcontractors that make the millions of parts that go into a modern sophisticated aircraft.

NORTHAM: Boeing says the aircraft deals will support nearly 100,000 U.S. jobs. But all that could be in jeopardy if the nuclear accord falls through. President Trump could refuse to certify that Iran is in compliance with the deal. It would then be up to Congress whether to impose sanctions which ultimately could scuttle the agreement. There's already a challenge from Congress.

(SOUNDBITE OF ARCHIVED RECORDING)

PETER ROSKAM: Mr. Chairman, I have an amendment at the desk.

UNIDENTIFIED MAN: Clerk will designate...

NORTHAM: Earlier this month, Representative Peter Roskam, a Republican from Illinois, put forth an amendment to block the sale of aircraft to Iran.

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ROSKAM: Iran's aviation sector, led by Iran Air, has a long history of illicitly transporting militants, weapons and explosives on commercial aircraft to terror groups and rogue regimes.

NORTHAM: The House passed the legislation. It's not clear if the Senate will follow suit. Farhad Alavi, a trade sanctions lawyer with the Akrivis Law Group, says, via Skype, the administration needs to think through the implications.

FARHAD ALAVI: It's not really a matter of simply shutting the door to a single sale or a couple sales to various Iranian airlines. But rather, what kind of signal does that send to the U.S. manufacturing sector?

NORTHAM: But Richard Aboulafia, an aviation analyst at the Teal Group, an aerospace consultancy, says the revenue opportunities for Boeing are being overblown.

RICHARD ABOULAFIA: It sounds important. It sounds geostrategic and earth-shaking. But in terms of actual commercial numbers, it's really not all that significant. You're talking about maybe a hundred planes for Boeing. And every year, they deliver over 700.

NORTHAM: But it's still worth billions of dollars, thousands of jobs, and Boeing could lose 30 to 40 years of market share to its fiercest competitor, Airbus. A Boeing official tells NPR it will comply with whatever the Trump administration decides about the Iran nuclear deal but says the same should apply to Airbus. Jackie Northam, NPR News.